Polar CS100 average speed does not seem accurate
Ally83
Posts: 3
Hi
I bought a polar cs100 computer and have been using it for a month now my average speed says 15mph or there abouts. I also use imapmyride on my iphone so that I can record the route on a map and noticed my average speed is about 23mph. So i decided to work it out for myself based on the miles I cycled and the time it took. The app seems more accurate. Has anyone else had this problem as both the computer and app are recording a similar distance and time but the computer seem to by way out with the average speed.
(last ride was 34.7miles and took 2 hours 20 minutes. Which I calculate to be an average speed off 24.78mph)
Maybe my calculations are incorrect
I bought a polar cs100 computer and have been using it for a month now my average speed says 15mph or there abouts. I also use imapmyride on my iphone so that I can record the route on a map and noticed my average speed is about 23mph. So i decided to work it out for myself based on the miles I cycled and the time it took. The app seems more accurate. Has anyone else had this problem as both the computer and app are recording a similar distance and time but the computer seem to by way out with the average speed.
(last ride was 34.7miles and took 2 hours 20 minutes. Which I calculate to be an average speed off 24.78mph)
Maybe my calculations are incorrect
0
Comments


Speed is distance divided by time taken. You may need to be careful how you express the time in the calculation because 2 hours 30 mins is 2.5 hours not 2.3 hours for instance.
Just trying to understand how you could have messed up the calculation.0 
I get 17.56mph.0

It's 14.87 mph as posted previously.
The manual calculation is....
34.7 miles divided by the number of minutes taken, in this case 140 minutes.
This gives you a distance of 0.24785714285714285714285714285714 miles travelled for each minute of the ride.
To give an average miles per hour you multiply by 60.
60 times 0.24785714285714285714285714285714 = 14.87“You may think that; I couldn’t possibly comment!”
Wilier Cento Uno SR/Wilier Mortirolo/Specialized Roubaix Comp/Kona Hei Hei/Calibre Bossnut0 
This is just silly. :P 2 hours 20 mins is 2.333 hours.
s=d/t
s=34.7/2.333
s=14.87 miles per hour :idea:
The comp is right, the app is wrong. Often GPS can be patchy of phones. The Polar should alow you to see your GPS accuracy  typicly about 24 ft on my Garmin 800, so it knows where I am + 8m. So on an 8m ride it may get my speed out by 100% but on a 50 km ride it is accurate to 0.016% of exact.
And with the greatest respect a 24mph average would have been very impressive over 35 miles, particulally if you are solo, which I assume you are as otherwise you would have asked a fellow ride their average. If you was capable of 24 mph you would dam well know it! 8)0 
Thanks guy realised I was converting the time into minutes and the app is giving the wrong units.
Feel like an idiot now lol0 
Was the app reading in km/h?
15mph ~ 24km/hMy bikes
MTB  1997 Kona Kula
Hybrid  Kona Dew Deluxe
Road  2011 Ribble Gran Fondo, Omega Matrix Ultegra0 
Now, if you had a bike computer that said you were averaging 24mph when doing 15mph you could make a few bob selling that on this forum.
Yeah I realise there are a few people with these already
This is intended to be humuorous and any similarity with real people is purely coincidental keep your toys in the prammy isetta is a 300cc bike0